Fossils reveal ancient walking bat species in New Zealand

"This helps us understand the capacity of bats to establish populations on islands and the climatic conditions required for this to happen," researcher Suzanne Hand said of the discovery.

Just as the newly discovered species of ancient bat did, New Zealand's modern bats scuttle about the forest floor on all fours. Photo by Rod Morris/UNSW

SYDNEY, June 17 (UPI) -- The fossils of an ancient bat were recently discovered in New Zealand, revealing a species that walked on four limbs and was three times larger than most modern bats.

The bat's remains were found on the nation's South Island in what was once a large prehistoric body of water called Lake Manuherikia. The fossils are between 16 and 19 million years old, meaning the bat lived during the early Miocene era and enjoyed a warmer subtropical rainforest habitat.

New Zealand only hosts three species of indigenous land mammals, all bats. The newly discovered species, Mystacina miocenalis, is closely related to two of the three species -- both from the same genus, (Mystacina).

One of the species, the Mystacina tuberculata, can still be found in New Zealand's old growth forests. The other (M. robusta) hasn't been seen since the late 1960s.

"Our discovery shows for the first time that Mystacina bats have been present in New Zealand for upwards of 16 million years, residing in habitats with very similar plant life and food sources," lead author Suzanne Hand, a vertebrate palaeontologist at Australia's University of New South Wales, said in a press release.

Like their ancient ancestor, New Zealand's surviving native bats also scuttle about the forest floor on all fours, digging for fallen fruits and insects buried in the leaves.

Though the ancient remains suggest the species shared a similar diet with its modern relatives, its body was much larger.

"The size of bats is physically constrained by the demands of flight and echolocation, as you need to be small, quick and accurate to chase insects in the dark," Hand said. "The unusually large size of this bat suggests it was doing less in-flight hunting and was taking heavier prey from the ground, and larger fruit than even its living cousin."

Researchers had hypothesized that New Zealand's bats had ancient origins, now there's proof.

"This helps us understand the capacity of bats to establish populations on islands and the climatic conditions required for this to happen," Hand added.